Download here: Ontario Curriculum Expectations
The most beautiful and most profound experience is the sensation of the mystical. It is the sower of all true science. He to whom this emotion is a stranger, who can no longer wonder and stand rapt in awe, is as good as dead. To know that what is impenetrable to us really exists, manifesting itself as the highest wisdom and the most radiant beauty which our dull faculties can comprehend only in their primitive forms – this knowledge, this feeling is at the center of true religiousness.
Albert Einstein
Famous People
Ancient people must have wondered why an object always fell to the ground if they released it from their hand. However, simply observing this phenomenon offered no explanation for it – it was a mystery. Galileo Galilei, an Italian scientist and mathematician who lived between 1564 and 1642, set out to solve this mystery. His work in mathematics, as well as the study of motion and forces, paved the way for many other famous scientists who used his work as the foundation for their own work. Sir Isaac Newton once stated, in reference to Galileo, that he had been able to see so far into the world of science because he had been “standing on the shoulders of giants.”
What is a force?
force is a push or a pull. We are applying a force to a lawn mower when we push it across the yard. We are applying a force in a game of tug-o-war when we pull on the rope.
The Effect of Forces:
Two things can happen when a force is exerted on an object:
- The force can change the motion of the object. It can cause the object to speed up, slow down, or change direction.
- Forces can change the shape of an object. It can make them smaller (compression) or it can make them larger (extension).
Watch this video to see some forces in action!
https://www.youtube-nocookie.com/embed/OKwet1Ue5Ic?rel=0&wmode=opaque
Measuring Forces:
We measure forces using the unit Newton (N) named after Sir Isaac Newton. Force is a vector quantity. It has a magnitude and a direction. The direction can be described using the directional coordinates (north, south, east, west) or with words like up, down, left, and right.
Examples of Force:
It takes 3 N of force to hold an apple in your hand.
It takes about 50 N of force to lift up a bowling ball.
It takes about 450 N of force to lift a 100-pound barbell.
NASA’s latest launch vehicle, the Delta 4 Heavy, develops a thrust of 7.3 million Newtons.